<?php
class SalesOrder {
	
	private $_id;
	private $_created;

	private $_items = array();
	
	public function __construct(){
		
	}
	
	public function get_id(){
		return $this->_id;
	}
	
	public function get_date_created(){
		return $this->_created;
	}
	
	public function get_items(){
		return $this->_items;
	}
	
	public function to_array(){
		$items = array();
		foreach($this->_items as $item){
			$items[] = array(
			// TODO to_array()
			);
		}
	}
}